Concentration Limits4 min read
Counting Carryover Preservative Hidden in Your Extracts
Preservatives riding in on hydrosols and plant extracts still count toward your limit, here is how to trace them.
April 18, 2026Read
Concentration Limits
Reading percentages, thresholds, and where a formula tips over a limit.
Concentration Limits4 min read
Total Essential Oil Load Versus Each Oil Individually
How to respect an overall essential-oil dermal ceiling and per-oil sensitizer limits in the same formula at once.
April 18, 2026Read
Concentration Limits3 min read
Ethylhexylglycerin Levels and Why It Boosts Not Preserves
Why ethylhexylglycerin can't carry a preservative system alone and how its typical level relates to phenoxyethanol pairing.
April 17, 2026Read
Concentration Limits4 min read
Formaldehyde-Releaser Preservatives and Their Thresholds
Releaser preservatives work by slowly emitting free formaldehyde, and that free formaldehyde level is what triggers a warning requirement.
April 14, 2026Read
Concentration Limits3 min read
Fragrance Allergen List 1 and the Percentages That Trigger It
The actual math behind List 1 fragrance allergen disclosure, with worked examples for leave-on and rinse-off products.
April 14, 2026Read
Concentration Limits4 min read
Diluting a 10 Percent Active Down to a Target Strength
The dilution math for cutting a 10 percent active stock down to a specific finished percentage, with a worked example and rounding caution.
April 12, 2026Read
Concentration Limits4 min read
How Concentration Sets Your Fragrance Allergen Triggers
The leave-on and rinse-off fragrance allergen thresholds in Canada hinge entirely on finished-product concentration math, not just ingredient presence.
April 11, 2026Read
Concentration Limits4 min read
Rounding Percentages the Right Way on a Formula Sheet
Rounding a restricted ingredient's percentage in the wrong direction can quietly understate it below a limit on paper while it sits over the limit in reality.
April 11, 2026Read
Concentration Limits4 min read
The Phenoxyethanol Limit and How to Check Yours
Phenoxyethanol has a permitted ceiling, and if it's arriving pre-blended with other preservatives, your real number needs a back calculation.
April 9, 2026Read
Concentration Limits3 min read
Menthol and Camphor Concentration Limits in Balms
Why cooling-agent concentration is the line between a cosmetic balm and a product that reads as a therapeutic drug claim.
April 7, 2026Read
Concentration Limits4 min read
CNF Concentration Range Brackets Cheat Sheet
The concentration range brackets you can use on a Canada CNF, plus a simple rule for placing borderline percentages.
March 31, 2026Read
Concentration Limits4 min read
Kojic Acid Concentration in Brightening Serums
Practical guidance on kojic acid levels in brightening serums and where hotlist restrictions and drug-claim lines can trip up a formula.
March 30, 2026Read
Concentration Limits4 min read
Reading a Preservative Blend TDS to Split the Percentages
Multiply each component's share by your use level to find its real concentration before checking it against Hotlist limits.
March 22, 2026Read
Concentration Limits3 min read
Mandelic Acid and Whether It Shares the AHA Limit
Mandelic acid is chemically an AHA, and makers formulating gentler exfoliants need to treat it with the same concentration discipline.
March 20, 2026Read
Concentration Limits4 min read
Sorbic Acid and Potassium Sorbate Concentration Limits
Sorbic acid and potassium sorbate are the same preservative in different forms, and converting between them correctly matters for your filing.
March 19, 2026Read
Concentration Limits3 min read
Benzoic Acid and Sodium Benzoate Limits Tied to pH
Why sodium benzoate's preservative ceiling and its actual effectiveness both come down to your formula's pH, not just the percentage on the label.
March 18, 2026Read
Concentration Limits4 min read
Cinnamon and Clove Oil Levels That Stay Skin-Safe
Why cinnamon and clove essential oils need a far lower usage ceiling than most essential oils, and how to keep strong sensitizers within safe range.
March 9, 2026Read
Concentration Limits3 min read
Glycolic Acid Percentage Where a Peel Stays Cosmetic
Where the concentration and pH line sits between an at-home glycolic acid product and something that crosses into professional-peel territory.
March 9, 2026Read
Concentration Limits4 min read
Why Weighing Beats Measuring Volume for Limit Accuracy
Volume measurements hide density differences that can push a restricted ingredient over its limit without you noticing.
March 7, 2026Read
Concentration Limits4 min read
Benzyl Alcohol as a Preservative Versus a Fragrance Note
Benzyl alcohol does two different jobs in a formula, and which one it's doing changes how you justify its percentage on a filing.
March 4, 2026Read
Concentration Limits4 min read
Combining an AHA and a BHA in One Formula Legally
How to track two separate acid concentration limits at once when a product carries both an AHA and a BHA.
February 27, 2026Read
Concentration Limits4 min read
Logging Ingredient Percentages So Your CNF Adds Up
A formula-sheet layout that keeps percentages summing to 100 and maps cleanly onto the concentration ranges Health Canada expects.
February 23, 2026Read
Concentration Limits4 min read
What w/w Percentage Actually Means on a Cosmetic Formula
Weight-by-weight percentage explained from first principles with a real gram-by-gram batch, so it stops getting confused with volume or drop counts.
February 23, 2026Read
Concentration Limits4 min read
Converting ppm to Percent Without Slipping a Decimal
The exact math for converting parts per million to percent, with worked examples for fragrance allergen thresholds and preservative limits.
February 21, 2026Read